Re: [lwip-users] dereferencing pointer to incomplete type in static LwIP library

[address@hidden]

Martin Osterloh wrote:
> I am new to LwIP and just started to play around with it. I wrote a 
> makefile to put LwIP into a static library. Compiling is no problem. 
> My sys_arch is not 100% complete yet (I still have to map mailboxes).
>
> However, I wrote a sample program to test LwIP. I can call sys_init() 
> or lwip_init() without problems.
>
> If I try to do:
>
> struct tcp_pcb *pcb;
> pcb->remote_port = 1024;
>
> for example, I get dereferencing errors.

What exactly do you mean by "dereferencing errors"?

> It seems that my program does not know anything about LwIP internals 
> (but I can call lwip_init() etc).

I'm confused. Which files did you include in lwip_test.c to use struct 
tcp_pcb?

> I use
>
> gcc lwip_test.c -o lwip_test -llwip
>
> to compile. The liblwip.a is in the same directory as the lwip_test.c.

The lib file does not tell the compiler what "struct tcp_pcb" is, you 
have to include "lwip/tcp.h" for that. I get the impression this is a 
problem in understanding the C language, not lwIP??

Simon